Algorithms are being developed and tested for aiding in numerical taxonomy of feature by strain matrices too large to be analyzed by existing programs. Both segmentation and heuristic approaches are being investigated. A program has been developed and is being used to compare and evaluate methods and/or laboratories when characterizing the same set of strains. The usual statistical packages are not useful because of the predominantly binary (i.e., discontinuous) nature of the data. The algorithm allows comparison of tests or laboratories at the levels of the individual strain (with replicable determinations), species, genus, and overall set for determination of test method equivalences and/or inter-laboratory consistency. Computer graphic algorithms are being tested to aid microbiologist in visualizing individual similarities as well as hierarchical group memberships among strains. Methods for interconversion between, and interrogation of, equivalent data bases with disparate formats (e.g., controlled vocabulary test versus numeric coding), are being developed as a necessary step in establishing an international Microbial Strain Data Network and for the Hybridoma Data Bank.